re: land the loop-point correction where the claim actually lives

The port found its exporter still shipping 'no loop-point field has been
identified anywhere' in the field manifest.json concatenates, days after the
correction existed in other fields. Auditing this corpus the same way found the
same failure here: the refuted sentence was still standing untouched in
bgm-two-stems.md -- where anyone looking up BGM behaviour arrives -- and in
HANDOFF.md, the one page the port is told to read. My correction had gone into a
NEW page only.

Both fixed in place, each naming the refutation rather than quietly deleting the
old claim, and each carrying the measured window [9.44, 71.31] s at 61.87 s.

METHOD entry: writing a correction down is not landing it. Grep the corpus for
the CLAIM, not for the file you were working in. Plus the port's trap in doing
that audit -- a replacement that quotes the refuted sentence in order to name it
will match a substring search from inside the paragraph saying it is false.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Wuu56cE8vJGTBtn1ppsk8v

docs/port/HANDOFF.md

@@ -1727,9 +1727,13 @@ discovered it after re-exporting. ❔ The sweeps may simply be a small term, and
   layer — 🟡 which of those is unsettled, and `ChannelMask` is `0x0002` on both,
   so the file will not say. Today's 347 s concatenation plays the piece twice,
   the second time as a bass-less stem.
-  ❔ **And it is not a seamless loop**: `BGM_001` fades out at 167.663 s and is
-  followed by 6.15 s of silence, with no loop-point field identified. A menu loop
-  is authored.
+  🔴 **"not a seamless loop … no loop-point field identified … a menu loop is
+  authored" — REFUTED 2026-08-30, and this bullet kept saying it for days after
+  the correction existed elsewhere.** The fade and the 6.15 s of silence are real,
+  but there **is** a loop point — in the **XMA decoder context**, set at runtime by
+  `XMASetLoopData`. For `BGM_103` it is **`[9.44 s, 71.31 s]`, cycling every
+  61.87 s**, watched over three wraps. The game never reaches the fade, which is
+  why the stored tail looked unusable. See the 2026-08-30 entries at the top.
   ✅ **The menu's music is `BGM_103`.** The cue *table* cannot say — its BGM
   entries are numeric — but `GamePart_Title`'s `sub_821C5580` plays **cue 1103**,
   and `BGM_103.slb`'s two declared waves (3 876 864 / 3 930 112 B) are

docs/re/METHOD.md

@@ -1431,3 +1431,31 @@ too — a span of zero cannot occur. Both cases point the same way:
 **The tell is in the rows that agree with you.** Scrutinising the disconfirming half
 harder is the intuitive discipline and it is the wrong half — a broken instrument
 and an easy control both fail *silently on the side you were hoping for*.
+
+## A correction that does not reach the artifact a consumer reads has not been made
+
+The port agent found that after correcting `loop_end_why` and `loop_start_why`, the
+field its exporter actually concatenates into `manifest.json` — `loop_why` — was
+**still shipping** "AUDIBLY WRONG AT THE SEAM" and "no loop-point field has been
+identified anywhere". Both refuted days earlier. Its corrections existed, were
+accurate, and were in the wrong fields.
+
+**And the same audit against this corpus found the same failure here.** The claim
+*"no loop-point field has been identified in the XMA header, so a menu loop is
+authored"* was refuted on 2026-08-30 — in a **new page**. The sentence stayed
+untouched in [`bgm-two-stems.md`](structures/bgm-two-stems.md), which is where
+anyone looking up BGM behaviour arrives, **and** in `HANDOFF.md`, which is the one
+page the port is told to read. A reader following either would have got the dead
+answer with nothing to warn them.
+
+⚠️ **Writing the correction down is not the same as landing it.** A new page records
+that you learned something; it does not stop the old sentence being read. When
+something is refuted, **grep the corpus for the claim, not for the file you were
+working in**, and fix it where it is stated — especially in `HANDOFF.md`, whose
+whole purpose is to be the page somebody reads instead of the rest.
+
+📌 And a trap in doing that audit, also the port's: its first verification reported
+the stale text **still present**, because the replacement *quotes* the refuted
+sentences in order to name them — so a substring search matches them inside the
+paragraph saying they are false. The match was real and meant the opposite of what
+the search implied. This is "the tell is in the rows that agree" arriving as a grep.

docs/re/structures/bgm-two-stems.md

@@ -117,11 +117,22 @@ transcribing one.
 * a music bank is **two waves that play together**, not one track and not a
   sequence — do not concatenate;
 * both are full length; align them at sample 0;
-* **the track is not a seamless loop.** `BGM_001` fades out and is followed by
-  **6.15 s of silence** (last sound 167.663 s of 173.809 s; the final second
-  before silence is at RMS 168 against 4 788 at the head). Looping the wave as
-  stored gives a fade-out and six seconds of nothing every cycle. No loop-point
-  field has been identified in the XMA header, so a menu loop is **authored**.
+* **the track is not a seamless loop *as stored*.** `BGM_001` fades out and is
+  followed by **6.15 s of silence** (last sound 167.663 s of 173.809 s; the final
+  second before silence is at RMS 168 against 4 788 at the head). Looping the wave
+  end-to-end gives a fade-out and six seconds of nothing every cycle.
+
+  🔴 **But "no loop-point field has been identified … so a menu loop is
+  authored" is REFUTED (2026-08-30), and this bullet said it for days after.**
+  There is no loop point in the **file header**; there is one in the **XMA decoder
+  context**, written at runtime via `XMASetLoopData`, and Xenia already logs it.
+  For `BGM_103` it is **`[9.44 s, 71.31 s]`, cycling every 61.87 s** — measured by
+  watching three wraps, so the game never reaches the fade at all. That is *why*
+  the stored tail looks unusable: it is never played.
+  [`menu-bgm-loop-fields-conflict.md`](menu-bgm-loop-fields-conflict.md)
+
+  ⚠️ Reach: measured on `BGM_103` only. Whether every bank carries loop bounds is
+  untested — but "the format has nowhere to put one" is dead.
 
 ## ✅ Confirmed at runtime — two stereo streams decode at once